[Qemu-devel] [PATCH] slirp: Propagate host TCP RST to the guest.

[Edgar E. Iglesias]

Hi,

Jason found a bug in teh slirp TCP RST code. Here is a patch to fix it.
Is this OK to commit?

Best regards
-- 
Edgar E. Iglesias
Axis Communications AB

When the host aborts (RST) it's side of a TCP connection we need to
propagate that RST to the guest. The current code can leave such guest
connections dangling forever. Spotted by Jason Wessel.

diff --git a/slirp/socket.c b/slirp/socket.c
index 75003af..bb10d69 100644
--- a/slirp/socket.c
+++ b/slirp/socket.c
@@ -165,9 +165,21 @@ soread(so)
                if (nn < 0 && (errno == EINTR || errno == EAGAIN))
                        return 0;
                else {
+                       int err;
+                       socklen_t slen = sizeof err;
+
+                       err = errno;
+                       if (nn == 0)
+                               getsockopt(so->s, SOL_SOCKET, SO_ERROR,
+                                          &err, &slen);
+
                        DEBUG_MISC((dfd, " --- soread() disconnected, nn = %d, 
errno = %d-%s\n", nn, errno,strerror(errno)));
                        sofcantrcvmore(so);
-                       tcp_sockclosed(sototcpcb(so));
+                       if (err == ECONNRESET
+                           || err == ENOTCONN || err == EPIPE)
+                               tcp_drop(sototcpcb(so), err);
+                       else
+                               tcp_sockclosed(sototcpcb(so));
                        return -1;
                }
        }